Final answer:
To determine the number of teams, use the expression 150/p, which divides the total number of players by the number of players on a team.
Step-by-step explanation:
To find the number of teams in the third round of playoffs when there is an equal number of players on each team (denoted as p), and there are 150 players in the league, we can use the expression 150/p. This expression divides the total number of players by the number of players on a team to give the total number of teams. Options A, C, and D are not suitable as they do not represent the correct method to calculate the number of teams.